Hypertension is one of the common medical complications of pregnancy and contributes significantly to the mother, unborn baby and the new born poor health condition and even death. Preeclampsia is a multi-system progressive disorder of unknown cause characterized by the new onset of hypertension to the extent of 140/90 mmHg or more on two or more occasion at least 4 to 6hours apart with significant proteinuria after the 20th week of pregnancy.
Also, the new onset of hypertension and significant end-organ dysfunction with or without proteinuria (presence of protein in the urine) in the last half of pregnancy or after delivery is also called preeclampsia.
Generally, it can be found in about 1 in 20 to 1 in 10 pregnancies. The condition usually resolves within 6weeks of delivery. If after the 12th week of delivery the blood pressure has not normalized, the individual is considered to have chronic hypertension (hypertension before pregnancy).
CAUSES OF PREECLAMPSIA
The cause of preeclampsia is unknown and how it comes to be in pregnancy is not well understood. There are a couple of theories that attempt to explain why it occur in individuals with the disease condition. The most common theory is that of failure to remodel the mother’s spiral arteries. This is due to failure of the baby’s part that contribute to the development of the placenta to properly invade the spiral arteries. There are however risk factors for preeclampsia and they include;
- Women who are pregnant for the first time
- Previous pregnancy complicated by preeclampsia
- Age >35 years or <18years
- Family history of preeclampsia
- Long standing hypertension
- Long standing kidney disease
- Autoimmune disease (disease in which the individual’s immune system attacks the body)
- Vascular disease (disease of blood vessels)
- Diabetes mellitus
- Pregnancy with two or more babies
- Sickle cell disease
- Black race
- Poorly controlled hyperthyroidism
- Women who were born small for gestational age
- In previous pregnancy; growth restricted baby while in the womb, premature separation of the placenta, death of the baby in the womb
- Prolonged inter-pregnancy interval (from one delivery to the next conception) >10years
- New partner or limited sperm exposure
- Pregnancy conceived via in vitro fertilization (IVF)
SYMPTOMS AND SIGNS OF PREECLAMPSIA
Apart from the new onset of elevated blood pressure and proteinuria, the clinical presentation depends on it severity. It is asymptomatic in mild preeclampsia and symptomatic with alarming symptoms in severe preeclampsia such as;
- Persistent and/or severe headache
- Visual abnormalities; loss of vision in some parts of the visual field or temporary blindness, excessive sensitivity of the eyes to light, blurred vision
- Upper right or upper middle abdominal pain
- Sleep disturbance
- Altered mental status
- New onset of difficulty in breathing
- Decrease urine output
TYPES OF PREECLAMPSIA
It is classified into mild preeclampsia or severe preeclampsia. In mild preeclampsia, the blood pressure is ≥140/90mmhg but < 160/110mmhg without any of the above symptoms and normal laboratory results. In severe preeclampsia, the blood pressure is ≥160/110mmhg with the above symptoms and abnormal laboratory result.
In addition, the preeclampsia that occurs before labour is called antepartum preeclampsia. If it occurs during labour it is called intrapartum preeclampsia. when it occur after delivery it is called post partum preeclampsia.
TREATMENT OF PREECLAMPSIA
The management of severe preeclampsia will involve doctors in different specialty (Obstetrician, Physician and the haematologist). The principle of treatment is by the use of certain medications to control the blood pressure, prevent seizures or treat seizures, manage fluid and electrolyte and plan for delivery after the mother is stabilize. Delivery of the placenta leads to resolution of both the clinical and biochemical manifestations of pre‐eclampsia.
The condition occurs due to faulty placenta formation. Women with preeclampsia with or without severe features can be delivered vaginally. Caesarean delivery is reserved for usual obstetrics indications. The decision to deliver depends on the severity of the disease condition and how old the pregnancy is. In severe cases, the doctor will advise termination of the pregnancy irrespective of how old is the pregnancy to save the mother’s life.
In mild cases after the period of viability (varies with region) but before maturity of the lungs (<35weeks), delivery might be delayed by most specialist to buy more time for the baby to achieve lung maturity. After delivery, women with this condition usually stay longer on admission than those without it. The aim is to ensure blood pressure is well controlled and any derangement in the laboratory result is corrected. Most women will be fit to go home between the 5th and 7th day after delivery.
COMPLICATIONS OF PREECLAMPSIA
This condition affect virtually all the body’s organs;
- In the brain: the patient can have seizure and or stroke.
- In the blood vessel: there may be formation of blood clot called deep vein thrombosis.
- In the lungs: there may be collection of fluid in the lungs called pulmonary oedema or the migration of blood clot formed in the blood vessels to the lungs called pulmonary embolism. This is fatal and can result in death within minutes if not identified on time and treated.
- In the heart: the patient can have heart attack called myocardial infarction.
- The liver might be damage
- The kidney might also be affected
- The patient clotting system that help to stop bleeding from a cut, bruise or punctured site might become deficient in doing so.
- Restriction of the baby’s growth in the womb
- Premature separation of the placenta (abruptio placentae)
- Death of the baby in the womb.
PREVENTION OF PREECLAMPSIA
When this condition occurs, it is an obstetrics emergency and a common cause of maternal death. Patient with preeclampsia in their previous pregnancy need to book for antenatal care early before 12weeks. Aspirin is usually given to such patient at 12weeks of pregnancy to prevent the occurrence in the index pregnancy. Also, calcium which is one of the routine antenatal medication has been shown to prevent preeclampsia.